StingerTM Explosion Isolation Valves

NFPA Compliant Inlet Protection

The Stinger explosion isolation valve prevents a deflagration (explosion) that could occur in the dust collector from traveling back down the inlet pipe back into the workspace/process.

Flow Activated Flap Valve

During normal operation, the airflow holds the blade open. A back stop makes sure the blade is in the approved and tested position. (Photo 1)

If a deflagration occurs in the dust collector, a pressure wave will travel through the pipe faster than the flame front and close the flap valve, protecting downstream personnel and equipment form injury and damage. (Photo 2)

When the valve is fully closed, a latching mechanism keeps it shut. The closed valve prevents the transmission of flame past the valve. (Photo 3)

The valve also prevents smoke, dust and burning debris from traveling through the inlet pipe into the factory. (Photo 4)

Composite Blade Advantages (Patent Pending)

The blades are made from a composite material for strength and minimum weight. Low weight is necessary for the valve to close with the highest possible speed. The design also eliminates the need for stiffeners on the back of the blade. Stiffeners allow dust build up on the blade, which increases the weight and thus, pressure required to hold the blade open. Dust on the back of the blade is also undesirable because it would provide additional fuel for the deflagration.

The front side of the blade is covered with a 3 mil abrasion resistant rubber sheeting. This does not contribute to the strength of the blade, but maintains it by protecting it from wear. Wear on a blade reduces its strength and could contribute to failure during a deflagration.

The wear liner also acts as a wear indicator. If the metal behind the liner is seen during routine inspections, it will indicate that the blade needs to be replaced. The valve seat is also replaceable but did not sustain damage during dozens of tests. The blades bolt to the square pivot shaft and are replaceable.

The Stinger explosion isolation valve features a fast acting composite blade that provides the following advantages:

Low weight

Lower pressure drop

Wear resistant liner

High strength to weight ratio

Smooth back

No dust accumulation

Easily replaceable

Absorbs damage evenly and protects main valve components from damage during activation